Low power and Lossy Networks (LLNs), e.g., sensor networks, have a myriad of applications, such as Smart Grid and Smart Cities. Various challenges are presented with LLNs, such as lossy links, low bandwidth, battery operation, low memory and/or processing capability, etc. One example routing solution to LLN challenges is a protocol called Routing Protocol for LLNs or “RPL,” which is a distance vector routing protocol that builds a Destination Oriented Directed Acyclic Graph (DODAG, or simply DAG) in addition to a set of features to bound the control traffic, support local (and slow) repair, etc. The RPL architecture provides a flexible method by which each node performs DODAG discovery, construction, and maintenance.
Many existing large-scale LLNs make use of source routing. To this end, RPL specifies a so-called Non-Storing mode, where only the root of the routing topology maintains the complete routing topology and uses source routing to deliver packets to nodes within the network. Further, Request for Comments (RFC) 6554 introduces mechanisms to compact the source route entries when all entries share the same prefix with the IPv6 destination address of a packet carrying a source route header (SRH), a typical scenario in LLNs using source routing. The compaction mechanism reduces consumption of scarce resources such as channel capacity.